Question

Find A,B,C where 5x^2 + Ax -7 = B(x+2)^2 + C
where A,B,C are constants

Answer 1

expanding the right side:-

5x^2 + Ax - 7 = Bx^2 +4Bx + 4B + C

Equating coefficients of x^2:-

B = 5

Equating coefficients of x:-

A = 4B
so
A = 4*5 = 20

Equating constants terms

-7 = 4B + C = 20 + C

C = - 27

A=20 , B = 5 and C = -27